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Choosing a boiler...

I'm purchasing a home in Duluth, MN. The existing oil fired boiler has issues and needs either to be repaired or replaced. I'm considering scrapping the unit and installing an LP system, since natural gas is not available in the area... yet.

The boiler feeds a baseboard system. I believe there are two or three existing zones.

Sizing:
I know I really should have a full blown heating test done. But, for now, I'm just looking for a solid estimate. The current oil boiler is 127,000 BTU. The house is 1800 sq feet. It's a split level. The split level (majority of sqft) was an addition, added in 1984.

I also want to add an indirect hot water heater. It's currently electric. I may opt to add this later though due to budgetary reasons.

After researching online, my gut is telling me that I'll need between 72,000 and 90,000 BTU.

Boiler:
I'm leaning towards the Weil-Mclain Ultra 105. It seems to have a lot of nice all-inclusive features. It's reasonably priced too. I'm also considering Buderus and Peerless, but am open to suggestions.

My main concern with the boiler is the type. I want to make sure I'm getting the correct specs. Based on a telephone call with one contractor, I'm somewhat concerned about aluminum. He was definitely suggesting stainless. He noted issues with premature leaking and start-up leaks. Anyone have similar concerns?

I guess my questions right now are:

At the ~90,000 BTU range, is it safe to say I'm close?

Does anyone have experience with the Weil-Mclain Ultra 105 in cold climates such as Duluth, MN?

Are there other brands/models/types of boilers I should be considering?

We don't get as cold as you. But the Ultra does fine at our low temps of 0 or just under.
If your baseboard is sized to heat your house at water temps under 200&#176;F, the Ultra will work fine for you.
As you probably saw, it comes with OD reset as standard.
It can be programed to do a quicker or slow water temp increase as the application needs.
As far as problems with the aluminum block. Nope. The Ultra comes with a 15 year warranty on the block. Most SS are 10, and 1 or 2 are 12 years.

Thanks for outlining the process. Unfortunately, I don't live in the house (or even the state) yet. But, this will be the first thing I do when I get there. One question: is it easy to tell the make/model of baseboards? I have never dealt with them before.

It's interesting that you mention Slant/Fin. My bother-in-law was touting Slant/Fin to me last night. Should I consider them? Are they all wall hanging? Or, do they have free standing boilers? The current boiler is freestanding next to the chimney. I figure it will be easiest to replace with a similar freestanding unit if I want to reuse the venting and plumbing as much as possible.

No mod/con boiler can reuse the venting of your existing boiler.
They can't be vented into a regular chimney.

Good to know! Should I abandon the mod/con boiler for another type to reuse the chimney? Or, look to other venting options? Basically, does the additional work for venting and possibly re-routing plumbing outweigh the benefits of mod/con?

If I don't go mod/con... what's the other type called? (Sorry, I'm new to this!)

mod/con boilers are direct vent. They vent either out the side of the building, or up through the roof in PVC pipe.
Your hydronic piping can be reused to an extent. (minor alterations)
Conventional would be what you would call other boilers, that are not condensing.

Your best bet, is to get prices for both. Then decide what you can afford to put in, and use.

Mod Cons

Depending on the water temperature that your system needs, a mod con MIGHT be an excellent choice.

I like Slant/Fin baseboard better than the others, but there are a LOT of good boiler companies with good boilers. I also am in the stainless steel camp, vs. the aluminum boilers, on a mod-con. Aluminum can dissolve too quickly, if something goes wrong inside.

Depending on the water temperature that your system needs, a mod con MIGHT be an excellent choice.

I like Slant/Fin baseboard better than the others, but there are a LOT of good boiler companies with good boilers. I also am in the stainless steel camp, vs. the aluminum boilers, on a mod-con. Aluminum can dissolve too quickly, if something goes wrong inside.

Noel

SS can rot out pretty quick if something goes wrong inside.

The OP can become a millionaire ovcer night if he buys the winning lottery ticket.

Noel.
How many Aluminum block mod/com boilers have you been involed with that dissolved? (not just heard about)